import java.util.Stack;

class Solution {
    public boolean isValid(String s) {
        Stack<Character> stack = new Stack<>();
        for(int i = 0; i < s.length(); i++){
            char ch = s.charAt(i);
            if(ch == '(' || ch == '{' || ch == '['){
                stack.push(ch);
            }else{
                if(stack.empty()){
                    return false;
                }

                char topl = stack.peek();
                if(topl == '(' && ch == ')' || topl == '{' && ch == '}'
                        ||topl == '[' && ch == ']' ){
                    stack.pop();
                }else{
                    return false;
                }
            }
        }
        if(!stack.empty()){
            return false;
        }
        return true;
    }
}